SECONDARY BATTERY

A secondary battery according to the present invention is provided with a positive electrode, a negative electrode and an electrolyte solution; the electrolyte solution contains water and a lithium salt; the negative electrode contains a negative electrode active material; a silane coupling agent, which is reductively decomposed at a potential that is higher than the reductive decomposition potential of water, is adhered to the surface of the negative electrode active material; and the silane coupling agent contains fluorine as a constituent element.